IPv6 maintenance Working Group (6man) F. Gont
Internet-Draft SI6 Networks / UTN-FRH
Updates: 2464, 2467, 2470, 4291 A. Cooper
(if approved) Cisco
Intended status: Standards Track D. Thaler
Expires: July 28, 2014 Microsoft
W. Liu
Huawei Technologies
January 24, 2014
Recommendation on Stable IPv6 Interface Identifiersdraft-ietf-6man-default-iids-00
Abstract
Stateless Address Autoconfiguration (SLAAC) for IPv6 typically
results in hosts configuring one or more stable addresses composed of
a network prefix advertised by a local router, and an Interface
Identifier that typically embeds a hardware address (e.g., an IEEE
LAN MAC address). The security and privacy implications of embedding
hardware addresses in the Interface Identifier have been known and
understood for some time now, and some popular IPv6 implementations
have already deviated from such schemes to mitigate these issues.
This document recommends [I-D.ietf-6man-stable-privacy-addresses] as
the default scheme for the generating stable IPv6 addresses and
recommends against embedding hardware addresses in IPv6 Interface
Identifiers.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on July 28, 2014.
Copyright Notice
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Internet-Draft Default Interface-IDs January 20141. Introduction
[RFC4862] specifies Stateless Address Autoconfiguration (SLAAC) for
IPv6 [RFC2460], which typically results in hosts configuring one or
more "stable" addresses composed of a network prefix advertised by a
local router, and an Interface Identifier (IID) [RFC4291] that
typically embeds a hardware address (e.g., an IEEE LAN MAC address).
The security and privacy implications of embedding a hardware address
in an IPv6 Interface ID have been known for some time now, and are
discussed in great detail in
[I-D.ietf-6man-ipv6-address-generation-privacy]; they include:
o Network activity correlation
o Location tracking
o Address scanning
o Device-specific vulnerability exploitation
Some popular IPv6 implementations have already deviated from the
traditional stable IID generation scheme to mitigate the
aforementioned security and privacy implications [Microsoft].
As a result of the aforementioned issues, this document recommends
the implementation of an alternative scheme
([I-D.ietf-6man-stable-privacy-addresses]) as the default stable
Interface-ID generation scheme, such that the aforementioned issues
are mitigated.
NOTE: [RFC4291] defines the "Modified EUI-64 format" for Interface
identifiers. Appendix A of [RFC4291] then describes how to transform
an IEEE EUI-64 identifier, or an IEEE 802 48-bit MAC address from
which an EUI-64 identifier is derived, into an interface identifier
in the Modified EUI-64 format.
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Internet-Draft Default Interface-IDs January 20142. Terminology
Stable address:
An address that does not vary over time within the same network
(as defined in [I-D.ietf-6man-ipv6-address-generation-privacy].
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
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Internet-Draft Default Interface-IDs January 20143. Generation of IPv6 Interface Identifiers
Nodes SHOULD NOT employ IPv6 address generation schemes that embed
the underlying hardware address in the Interface Identifier. Namely,
nodes SHOULD NOT generate Interface Identifiers with the schemes
specified in [RFC2464], [RFC2467], and [RFC2470].
Nodes SHOULD implement and employ
[I-D.ietf-6man-stable-privacy-addresses] as the default scheme for
generating stable IPv6 addresses with SLAAC.
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Internet-Draft Default Interface-IDs January 20144. IANA Considerations
There are no IANA registries within this document. The RFC-Editor
can remove this section before publication of this document as an
RFC.
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